The present invention relates to the making of a corrugated, copper-stabilized Nb.sub.3 Sn superconductor.
Nb.sub.3 Sn is a superconductive compound which is highly suitable for cryogenic current conduction because its transition temperature of about 18.degree. Kelvin is, for this material, unusually high and can, therefore, be readily operated with.
U.S. Pat. No. 3,866,315 and German printed patent application No. 2,443,226 relate to methods of making such a superconductor; a ribbon of niobium is worked in that copper particles are brushed onto the ribbon and, thereafter, a thick copper layer is electroplated onto the ribbon. Next, the ribbon is longitudinally folded in order to obtain a split tube, welded along its edges, and the resulting tube is corrugated. Thereafter, a tin layer is deposited onto the niobium and annealed in a vacuum for obtaining the compound Nb.sub.3 Sn in the interface of tin and niobium. A problem has arisen here concerning the depositing of the tin layer which should be thin, but must be continuous, without any holes or weak spots because the Nb.sub.3 Sn layer should be as uniform as possible for the purpose of obtaining a uniform current density in cryogenic use.